全文获取类型
收费全文 | 2602761篇 |
免费 | 186224篇 |
国内免费 | 7593篇 |
专业分类
耳鼻咽喉 | 34502篇 |
儿科学 | 85602篇 |
妇产科学 | 71869篇 |
基础医学 | 365684篇 |
口腔科学 | 70265篇 |
临床医学 | 236088篇 |
内科学 | 518644篇 |
皮肤病学 | 62581篇 |
神经病学 | 215098篇 |
特种医学 | 100513篇 |
外国民族医学 | 737篇 |
外科学 | 388195篇 |
综合类 | 50659篇 |
现状与发展 | 5篇 |
一般理论 | 987篇 |
预防医学 | 197480篇 |
眼科学 | 57108篇 |
药学 | 189147篇 |
8篇 | |
中国医学 | 5341篇 |
肿瘤学 | 146065篇 |
出版年
2021年 | 20178篇 |
2019年 | 20822篇 |
2018年 | 29482篇 |
2017年 | 22758篇 |
2016年 | 26438篇 |
2015年 | 29742篇 |
2014年 | 40789篇 |
2013年 | 61140篇 |
2012年 | 81039篇 |
2011年 | 85351篇 |
2010年 | 51479篇 |
2009年 | 49612篇 |
2008年 | 79880篇 |
2007年 | 84827篇 |
2006年 | 86579篇 |
2005年 | 82753篇 |
2004年 | 79651篇 |
2003年 | 76910篇 |
2002年 | 74261篇 |
2001年 | 128592篇 |
2000年 | 131502篇 |
1999年 | 110686篇 |
1998年 | 31494篇 |
1997年 | 28130篇 |
1996年 | 28402篇 |
1995年 | 27569篇 |
1994年 | 25234篇 |
1993年 | 23564篇 |
1992年 | 85314篇 |
1991年 | 81704篇 |
1990年 | 78934篇 |
1989年 | 76192篇 |
1988年 | 69633篇 |
1987年 | 68144篇 |
1986年 | 63677篇 |
1985年 | 60637篇 |
1984年 | 45082篇 |
1983年 | 38068篇 |
1982年 | 22631篇 |
1981年 | 20168篇 |
1979年 | 39083篇 |
1978年 | 27537篇 |
1977年 | 23349篇 |
1976年 | 21575篇 |
1975年 | 22902篇 |
1974年 | 26870篇 |
1973年 | 25435篇 |
1972年 | 23813篇 |
1971年 | 22015篇 |
1970年 | 20232篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Ian M. Windmill 《中国听力语言康复科学杂志》2015,(1)
随着婴儿潮、人口老龄化及新技术的广泛应用,人们对听力保健的需求显著增加。在美国,听力保健服务由助听设备专员、耳鼻喉科医生和听力师3类人员提供,其中听力师提供除医疗、手术外宽泛的听力保健服务。美国的听力保健服务体系及听力师教育体系经历了一个渐进的过程:20年前对从业人员的学历要求是听力学硕士,随着对服务质量要求的提高和服务范围的扩大,美国听力师逐渐要求专业博士学位(Au.D),毕业后还需3~4年的专门教育才能成为一名听力师。听力师教育有统一的标准,大学课程要通过听力教育认证委员会(the Accreditation Commission for Audiology Education, ACAE)或学术认证委员会(the Council on Academic Accreditation,CAA)的多程序严格的认证才能被承认。美国听力师需求存在巨大缺口,但是各国听力学教育标准不统一及听力师收入与教育投资不匹配,阻碍了更多的人进入这一领域。美国试图通过改变教育模式,降低教育成本及革新教学方法等改善听力师教育状况,但是听力师教育体系远未完善。 相似文献
12.
13.
Sarah Averbach Othman Kakaire Rachel McDiehl Christine Dehlendorf Felicia Lester Jody Steinauer 《Contraception》2019,99(2):87-93
Objective
This study assessed whether immediate postpartum insertion of levonorgestrel contraceptive implants is associated with a difference in infant growth from birth to 6 months, onset of lactogenesis, or breastfeeding continuation at 3 and 6 months postpartum compared to delayed insertion at 6 to 8 weeks postpartum.Study design
We conducted a randomized trial of women in Uganda who desired contraceptive implants postpartum. We randomly assigned participants to receive either immediate (within 5 days of delivery) or delayed (6 to 8 weeks postpartum) insertion of a two-rod levonorgestrel contraceptive implant system. This is a prespecified secondary analysis evaluating breastfeeding outcomes. The primary outcome of this secondary analysis was change in infant weight; infants were weighed and measured at birth and 6 months. We used a validated questionnaire to assess onset of lactogenesis daily in person while participants were in the hospital, and then daily by phone after they left the hospital, until lactogenesis was documented. We used interviewer-administered questionnaires to assess breastfeeding continuation and concerns at 3 months and 6 months postpartum.Results
Among the 96 women randomized to the immediate group and the 87 women to the delayed group, the mean change in infant weight from birth to 6 months was similar between groups: 4632?g in the immediate group and 4407?g in the delayed group (p=.26). Among the 97 women who had not experienced lactogenesis prior to randomization, the median time to onset of lactogenesis did not differ significantly between the immediate and delayed groups (65?h versus 63?h; p=.84). Similar proportions of women in the immediate and delayed groups reported exclusive breastfeeding at 3 months (74% versus 71%; p=.74) and 6 months (48% versus 52%; p=.58).Conclusion
We found no association between the timing of postpartum initiation of levonorgestrel contraceptive implants and change in infant growth from birth to 6 months, onset of lactogenesis, or breastfeeding continuation at 3 or 6 months postpartum.Implications
This study provides evidence that immediate postpartum initiation of contraception implants does not have a deleterious effect on infant growth or initiation or continuation of breastfeeding. 相似文献14.
Josh Greenstein Devjani Das Josie Acuna Monica Kapoor Cara Brown Abbas Husain Brendan Lally Barry Hahn 《The American journal of emergency medicine》2019,37(2):313-316
Background
In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.Objectives
The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.Methods
This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.Results
A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.Conclusions
In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation. 相似文献15.
M. Iachina P.M. Ljungdalh R.G. Sørensen L. Kaerlev J. Blaakær O. Trosko N. Qvist B.M. Nørgård 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(2):115-123
Aims
To examine the influence of pre-existing psychiatric disorder on the choice of treatment in patients with gynaecological cancer.Materials and methods
The analyses were based on all patients who underwent surgical treatment for endometrial, ovarian or cervical cancer who were registered in the Danish Gynecological Cancer Database in the years 2007–2014 (3059 patients with ovarian cancer, 5100 patients with endometrial cancer and 1150 with cervical cancer). Logistic regression model and Cox regression model, adjusted for relevant confounders, were used to estimate the effect of pre-existing psychiatric disorder on the course of cancer treatment. Our outcomes were (i) presurgical oncological treatment, (ii) macroradical surgery for patients with ovarian cancer, (iii) radiation/chemotherapy within 30 days and 100 days after surgery and (iv) time from surgery to first oncological treatment.Results
In the group of patients with ovarian cancer, more patients with a psychiatric disorder received macroradical surgery versus patients without a psychiatric disorder, corresponding to an adjusted odds ratio of 1.24 (95% confidence interval 0.62–2.41) and the chance for having oncological treatment within 100 days was odds ratio = 1.26 (95% confidence interval 0.77–2.10). As for patients with endometrial cancer, all outcome estimates were close to unity. The adjusted odds ratio for oncological treatment within 30 days after surgery in patients with cervical cancer with a history of psychiatric disorder was 0.20 (95% confidence interval 0.03–1.54).Conclusions
We did not find any significant differences in the treatment of ovarian and endometrial cancer in patients with pre-existing psychiatric diagnoses. When it comes to oncological treatment, we suggest that increased attention should be paid to patients with cervical cancer having a pre-existing psychiatric diagnosis. 相似文献16.
Background
Total knee arthroplasty is a treatment option for debilitating arthritis. In the postoperative period, patients experience moderate to severe pain affecting the rehabilitation, hospital stay, and patient satisfaction. This study aims at utilizing current best evidence to determine whether adductor canal block (ACB) or periarticular injection (PAI) is a better modality for managing short-term postoperative pain and opioid consumption.Methods
Embase, MEDLINE, HealthStar, Emcare, and PubMed were searched for randomized controlled trials from 1946 to August 2018, for literature addressing the comparison of ACB and PAI for pain management in the setting of total knee arthroplasty. A systematic review and meta-analysis were performed.Results
Six studies were included in our meta-analysis. When examining the combined visual analog scale (VAS) pain values for each group, analysis demonstrated greater reduction in scores for the PAI group, and the difference was statistically significant (P = .001). When comparing the VAS scores of subgroups analyzed at specific periods in time, there was a trend toward lower VAS scores in subgroups analyzed at 24 hours and 48 hours postoperatively (at rest and at movement) in the PAI group. Overall opioid consumption was lower in the PAI group, with demonstrated statistical significance (P = .03). When comparing the postoperative subgroups, there was a trend toward decreased opioid use in the PAI group, with 13.25% less opioid use at 48 hours and 9.5% less opioid use at 24 hours.Conclusion
PAI could significantly improve postoperative pain and opioid consumption when compared with ACB. Additional, high-quality studies are required to further address this topic. 相似文献17.
Katherine M. Duszynski Nicole L. Pratt John W. Lynch Jesia G. Berry Michael S. Gold 《Vaccine》2019,37(2):280-288
Objective
To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.Design
Observational nationwide cohort study.Setting
Linked population data from the Australian Childhood Immunisation Register and National Death Index.Participants
Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.Main outcome measures
Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.Results
The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.Conclusion
Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality. 相似文献18.
Srdan Verstovsek MD PhD Jean-Jacques Kiladjian MD PhD Alessandro M. Vannucchi MD Ruben A. Mesa MD FACP Peg Squier MD PhD J. E. Hamer-Maansson MSPH Claire Harrison MD 《Cancer》2023,129(11):1681-1690
Background
In a pooled analysis of the phase 3 Controlled Myelofibrosis Study With Oral JAK Inhibitor Treatment I (COMFORT-I) and COMFORT-II clinical trials, adult patients with intermediate-2 or high-risk myelofibrosis who received oral ruxolitinib at randomization or after crossover from placebo or best available therapy (BAT) had improved overall survival (OS).Methods
This post hoc analysis of pooled COMFORT data examined relevant disease outcomes based on the disease duration (≤12 or >12 months from diagnosis) before ruxolitinib initiation.Results
The analysis included 525 patients (ruxolitinib: ≤12 months, n = 84; >12 months, n = 216; placebo/BAT: ≤12 months, n = 66; >12 months, n = 159); the median age was 65.0–70.0 years. Fewer thrombocytopenia and anemia events were observed among patients who initiated ruxolitinib treatment earlier. At Weeks 24 and 48, the spleen volume response (SVR) was higher for patients who initiated ruxolitinib earlier (47.6% vs. 32.9% at Week 24, p = .0610; 44.0% vs. 26.9% at Week 48, p = .0149). In a multivariable analysis of factors associated with spleen volume reduction, a logistic regression model that controlled for confounding factors found that a significantly greater binary reduction was observed among patients with shorter versus longer disease duration (p = .022). At Week 240, OS was significantly improved among patients who initiated ruxolitinib earlier (63% [95% CI, 51%‒73%] vs. 57% [95% CI, 49%‒64%]; hazard ratio, 1.53; 95% CI, 1.01‒2.31; p = .0430). Regardless of disease duration, a longer OS was observed for patients who received ruxolitinib versus those who received placebo/BAT.Conclusions
These findings suggest that earlier ruxolitinib initiation for adult patients with intermediate-2 and high-risk myelofibrosis may improve clinical outcomes, including fewer cytopenia events, durable SVR, and prolonged OS.Plain Language Summary
- Patients with myelofibrosis, a bone marrow cancer, often do not live as long as the general population. These patients may also have an enlarged spleen and difficult symptoms such as fatigue.
- Two large clinical trials showed that patients treated with the drug ruxolitinib lived longer and had improved symptoms compared to those treated with placebo or other standard treatments.
- Here it was examined whether starting treatment with ruxolitinib earlier (i.e., within a year of diagnosis) provided benefits versus delaying treatment.
- Patients who received ruxolitinib within a year of diagnosis lived longer and experienced fewer disease symptoms than those whose treatment was delayed.
19.
20.